Drafting mechanism for textile fibers



NOV. 13, 1945. J. NOGUERA 2,388,760

DRAFTING MECHANISM FOR TEXTILE FIBERS Filed Dec. 15, 1942 Attorney? Patented Nov. 13, 1945 DB-AFIING MECHANISM FOR TEXTILE FIBERS Joseph Nognera, Prestwich, Manchester, England, asslgnor to Casablanca High Draft Company Limited, 1

Manchester, England, a British com- In Great Britain December 1, 1941 Application December-15,1942, semi No. 469,101

ZClaims. (01. 19-130) This invention relates to drafting mechanisms for textile fibers of the type in which the fiber passes between each of three or more pairs of rollers, the intermediate pair or pairs of rollers acting as drawing rollers with respect to the preceding pair and as retaining rollers with respect to the succeeding pair.

In a normal mechanism of this type, the superposed axes of the pairs of rollers lie in parallel planes, while the nips of the pairs of rollers are in substantial alignment. With-this type of mechanism the amount of draft which draw-frames and speed-frames in cotton spin-- ning, the dimculty is increased because, owing to In machines where Figure 1 illustrates a drafting'mechanism according to the invention consisting of three pairs 01', rollers. I

Figure 2 also illustrates a drafting mechanism consisting of three pairs of rollers but diflerently arranged.

- .Figure 3 illustrates a drafting mechanism consisting of five pairs of rollers.

Thus, in its simplest embodiment, as illustrated in Figure 1 of the accompanying draw- I ing, a drafting mechanism according to the the considerable interfiber-adhesion in the thick strand, the distance between two consecutive pairs of rollers has to be substantially greater than the length of the longest fibers. The result is that between the two pairs of rollers, that is, in the space where the drafting takes place,

the strand is almost entirely uncontrolled, and is therefore apt to yield to the pull of the drafting rollers in a haphazard and irregular manner. The nip formed by each pair of rollers is also unsatisfactory when dealing with a large bulk of fiber because whilst the centre or core of the strand is squeezed or trapped hard in between the two rollers, numerous fibers are leftv on either side of the almond-shaped cross-section of the strand which are not held sufliciently or are not held at all. This applies to each pair of rollers both in connection with their retaining action and with their drawing action.

The invention provides a drafting mechanism in which the rollers are disposed in such manner that the drawing action and/or the retaining action of the rollers are much improved, especially in the drafting of very thick strands of fiber.

According to the invention, in a drafting mechanism of the type described, the rollers arearranged in such manner that the plane containing the axes of one pair of rollers-is at right angles to the plane containing the axes of the preceding and succeeding pairs respectively, whereby the strand on leaving each of two consecutive pairs of rollers is pulled round over about a quarter of the surface of one of the rollers of each pair, after which it passes-straight into the nip of the succeeding pair.

In the accompanying diagrammatic drawing:

present invention consists of three pairs of rollers i, la, 2, 2a and 3, 3a. The'strand 4' on leaving the pair of rollers I, la is pressed against about a quarter of the surface of the roller la before passing straight into the nip of the pair of rollers 2, 20,. Similarly, the strand on leaving the pair of rollers 2, 2a is pressed against about a quarter of the surface of the roller 2a before passing straight into the nip oi the pair of rollers 3, 3a.

v The three pairs of rollers I, la, '2, 2a and 3, 3 may also be arranged as shown in Figure 2 of the accompanying drawing, which is self-explanatory.

A drafting mechanism according to the present invent on consisting of five pairs of rollers is illustrated in Figure 3 01 the accompanying drawing.

In these arrangements according to the invention the strand of fiber is pressed against one of the rollers of each of at least two consecutive pairs for about of its surface, and .a very substantial measure of effective, yet yielding, fiber control is afforded. The drawing action of the intermediate pairs ofrollers is made more eificient because as the drawn fibers are subsequently pulled around one of the rollers, they tighten amongst themselves and this assists in compelling forward the whole strand.

What I claim and desire to secure by Patent of the United States is:

1, A drafting mechanism for textile fibers of the type in which the strand of fibers passes between each of three pa rs of rollers. the intermediate pair of rollers acting as drawing rollers with respect to the preceding pair and as retaining rollers with respect to the succeeding pair, in which the rollers are arranged in such manner that the plane containing theaxes of the intermediate pair of rollers is at right angles to the planes containing the axes of the preceding and succeeding pairs respectively, whereby the strand on leaving each of the first two pairs of rollers is pulled round over about a quarter of the Letters 2 asssnso surface of one of the rollers 01' each pair, after which it passes straight into the nip of the succeedins pair.

2. A drafting mechanism for textile fibers or the type in which the strand 0! fibers passes between at least three pairs oi rollers, the intermediate pairs of rollers acting asdrawing rollers with respect to the preceding pair and as retaining rollers with respect to the succeeding pair, in which the rollers are arranged in such manner that the plane containing the axes of any pair v of rollers except the first and. last pairs is at right angles to the plane containing the axes of the immediately preceding and succeeding pairs respectively, wherebyithe strand on leaving each of two consecutive pairs of rollers but not including the last pair is pulled round over about a quarter oi. the surface 0! one oi. the rollers of each pair, after which it passes straight into the nip 0! the succeeding pair.

JOSEPH NOGUERA. 

